Epidemics in Space: Control, Targeting and Delegation

We analyse optimal disease mitigation in a spatial model where disease spreads within and between interconnected regions. We characterise optimal strategies and emphasise the role of inter-regional coordination and policy targeting. Delegation of policy to regional planners achieves targeting without coordination, while a centrally determined uniform policy achieves coordination without targeting; both induce inefficiencies. For strongly connected regions, policy coordination is paramount, while for weakly connected regions, targeting becomes more important. Last, we analyse the value of reductions in integration, such as travel restrictions. We show that these may be non-monotone and sensitive to the underlying mitigation policy in place.